From the mode-marching method,by doing some transforms and derivations,the scatteringand propagation integral equations for solving the problems of discontinuous dielectric structure are ob-tained.The necessary and su...From the mode-marching method,by doing some transforms and derivations,the scatteringand propagation integral equations for solving the problems of discontinuous dielectric structure are ob-tained.The necessary and sufficient condition for the existence of solution of propagating equations is giv-en.It is really the dispersion equation of the dielectric structure.As an example,a succinct solution ofone-step discontinuous dielectric structure is derived.展开更多
Corrosion can be very harmful to the service life and several properties of reinforced concrete structures.The metal magnetic memory(MMM)method,as a newly developed spontaneous magnetic flux leakage(SMFL)non-destructi...Corrosion can be very harmful to the service life and several properties of reinforced concrete structures.The metal magnetic memory(MMM)method,as a newly developed spontaneous magnetic flux leakage(SMFL)non-destructive testing(NDT)technique,is considered a potentially viable method for detecting corrosion damage in reinforced concrete members.To this end,in this paper,the indoor electrochemical method was employed to accelerate the corrosion of outsourced concrete specimens with different steel bar diameters,and the normal components Bz and its gradient of the SMFL fields on the specimen surfaces were investigated based on the metal magnetic memory(MMM)method.The experimental results showed that the SMFL experimental Bz curves are consistent with the analytical results of the theoretical model.Furthermore,the crest-to-trough behavior on the Bz signal curve and its zero-point gradient spacing can more accurately indicate the corroded area’s extent.Then,a magnetic characteristic parameter W based on a large amount of experimental data was established to characterize the degree of corrosion of the steel bars.The magnetic characteristic parameter W is linearly related to the maximum cross-sectional area loss rateof the corroded reinforcement.This paper will lay the foundation for future research on corrosion detection of reinforced concrete structures based on the MMM method and provide a feasible way for non-destructive detection of corrosion independent of the influence of reinforcement diameter and magnetization history.展开更多
A systematic algorithm is set up with vertical numerical mode-matching method to findthe Green’s function of static-steady field in the 2-D axial symmetric inhomogeneous me-dia. The formultion is given totally in mat...A systematic algorithm is set up with vertical numerical mode-matching method to findthe Green’s function of static-steady field in the 2-D axial symmetric inhomogeneous me-dia. The formultion is given totally in matrix forms, which could be treated easily withmicrocomputers. Furthermore, no numerical integration is needed throughout thesimulation process. The efficiency of the algorithIn can be about 100 times higher that ofthe 2-D finite element method. The vertical numerical mode-matching tecgnique is pro-展开更多
文摘From the mode-marching method,by doing some transforms and derivations,the scatteringand propagation integral equations for solving the problems of discontinuous dielectric structure are ob-tained.The necessary and sufficient condition for the existence of solution of propagating equations is giv-en.It is really the dispersion equation of the dielectric structure.As an example,a succinct solution ofone-step discontinuous dielectric structure is derived.
文摘Corrosion can be very harmful to the service life and several properties of reinforced concrete structures.The metal magnetic memory(MMM)method,as a newly developed spontaneous magnetic flux leakage(SMFL)non-destructive testing(NDT)technique,is considered a potentially viable method for detecting corrosion damage in reinforced concrete members.To this end,in this paper,the indoor electrochemical method was employed to accelerate the corrosion of outsourced concrete specimens with different steel bar diameters,and the normal components Bz and its gradient of the SMFL fields on the specimen surfaces were investigated based on the metal magnetic memory(MMM)method.The experimental results showed that the SMFL experimental Bz curves are consistent with the analytical results of the theoretical model.Furthermore,the crest-to-trough behavior on the Bz signal curve and its zero-point gradient spacing can more accurately indicate the corroded area’s extent.Then,a magnetic characteristic parameter W based on a large amount of experimental data was established to characterize the degree of corrosion of the steel bars.The magnetic characteristic parameter W is linearly related to the maximum cross-sectional area loss rateof the corroded reinforcement.This paper will lay the foundation for future research on corrosion detection of reinforced concrete structures based on the MMM method and provide a feasible way for non-destructive detection of corrosion independent of the influence of reinforcement diameter and magnetization history.
基金Project supported by the National Natural Science Foundation of China.
文摘A systematic algorithm is set up with vertical numerical mode-matching method to findthe Green’s function of static-steady field in the 2-D axial symmetric inhomogeneous me-dia. The formultion is given totally in matrix forms, which could be treated easily withmicrocomputers. Furthermore, no numerical integration is needed throughout thesimulation process. The efficiency of the algorithIn can be about 100 times higher that ofthe 2-D finite element method. The vertical numerical mode-matching tecgnique is pro-
